Thixotropic aqueous solutions containing a crosslinked polygalactomannan gum

Claim 2

A process for preparing a thixotropic aqueous solution which comprises treating an aqueous medium with a thickening agent comprising (1) polygalactomannan gum, (2) between about 1-10 millimoles of diglycidyl ether of polyoxyalkylene diol per mole of polygalactomannan gum, and (3) a water-soluble basic reagent.

Claim 3

A process in accordance with claim 1 wherein the polygalactomannan gum is guar gum or an ether derivative of guar gum.

Claim 4

A process in accordance with claim 1 wherein the polygalactomannan gum is locust bean gum or an ether derivative of locust bean gum.

Claim 5

A process in accordance with claim 1 wherein the basic reagent is an inorganic salt.

Claim 6

A process in accordance with claim 1 wherein the basic reagent is an alkali metal salt.

Claim 7

A process in accordance with claim 1 wherein the basic reagent is alkali metal hydroxide.

Claim 8

A process in accordance with claim 1 wherein the basic reagent is alkali metal carbonate.

Claim 9

A process in accordance with claim 1 wherein diglycidyl ether crosslinking of polygalactomannan gum occurs in the aqueous solution at a pH above about 7.

Claim 10

A process for producing a thixotropic aqueous solution containing crosslinked polygalactomannan gum which comprises dissolving in an aqueous medium constituents comprising (1) polygalactomannan gum, (2) between about 1-10 millimoles of diglycidyl ether of polyoxyalkylene diol per mole of polygalactomannan gum, and (3) a water-soluble basic reagent; wherein the product thixotropic solution at a 1.0 weight percent content level of the polygalactomannan gum exhibits a viscosity of 10,000-120,000 centipoises at a shear rate of 0.3 reciprocal seconds, a viscosity of 300-10,000 centipoises at a shear rate of 5 reciprocal seconds, and a viscosity of 50-300 centipoises at a shear rate of 500 reciprocal seconds, and wherein the solution has the ability to recover the low-shear high-viscosity state over an elapsed time period.

Claim 11

A process for producing a thixotropic aqueous solution containing crosslinked polygalactomannan gum which comprises dissolving in an aqueous medium constituents comprising (1) polygalactomannan gum, (2) between about 1-10 millimoles of diglycidyl ether of polyoxyalkylene diol per mole of polygalactomannan gum, and (3) a water-soluble basic reagent; wherein the product thixotropic solution at a 1.0 weight percent content level of the polygalactomannan gum exhibits a viscosity of 10,000-120,000 centipoises at a shear rate of 0.3 reciprocal seconds, a viscosity of 300-10,000 centipoises at a shear rate of 5 reciprocal seconds, and a viscosity of 50-300 centipoises at a shear rate of 500 reciprocal seconds, and wherein the solution has the ability to recover the low-shear high-viscosity state over an elapsed time period.

Claim 12

A thixotropic aqueous solution produced in accordance with the process of claim 9.

Claim 13

A thixotropic aqueous solution containing a thickening agent comprising polygalactomannan gum which is crosslinked with a diglycidyl ether of polyoxyalkylene diol.

Claim 14

A thixotropic aqueous solution containing a thickening agent comprising polygalactomannan gum which is crosslinked with a diglycidyl ether of polyoxyalkylene diol.

Claim 15

A thixotropic aqueous solution in accordance with claim 11 wherein the polygalactomannan gum is guar gum.

Claim 16

A thixotropic aqueous solution in accordance with claim 11 wherein the polygalactomannan gum is locust bean gum.

Claim 17

A thixotropic aqueous solution in accordance with claim 11 wherein the diglycidyl ether of polyoxyalkylene diol corresponds to the formula: ##STR4## where R is hydrogen or an alkyl substitutent containing between about 1-4 carbon atoms, and n is an integer between about 1-100.

Claim 18

A water-soluble composition consisting of a polygalactomannan gum which is crosslinked by reaction with about 1-10 millimoles of a diglycidyl ether of polyoxyalkylene diol corresponding to the formula: ##STR5## where R is hydrogen or an alkyl substituent containing between about 1-4 carbon atoms, and n is an integer between about 1-100.

Claim 19

A water-soluble composition consisting of a polygalactomannan gum which is crosslinked by reaction with about 1-10 millimoles of a diglycidyl ether of polyoxyalkylene diol corresponding to the formula: ##STR5## where R is hydrogen or an alkyl substituent containing between about 1-4 carbon atoms, and n is an integer between about 1-100.